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erratic injection pressure isnt likely caused by the temp, however if the oil temp is whats running up then the LPOP pressure can drop off low enough that it cant pump the HPOP full and you'll shut down.. however id expect in the tattle tales section of the servicemaxx parameters youd see oil pressure faults and temperature faults..
it could be that your ICP sensor or the wiring around it is not right which would cause the erratic pressure code and could easily stall the engine..
ive not see na condition where high temp will shut it down.. though it should turn on the red oil / water light and the beeper.. and of course the gauge is off the scale.. the temp gauge on the dash is tied to the water temperature sender that gets sent to the ECM...
there is a second sensor which is oil T.. and that can also trigger engine de-rates.. but im not sure to what extent it does.. ive never faked that sensor out to see what it does at various temps...
your Injection pressure (injection pressure is oil pressure)is controlled by 4 things..
1. oil Supply - the supply of oil to the HPOP by the main oil pump or LPOP (lube pressure oil pump).. the dash gauge is LPOP.. if that goes to 0 or close to it then you'll not be able to supply the injection oil pressure..
2. HPOP - the HPOP itself needs to be able to reach the required pressures and supply sufficient volume of oil at those pressures.. if that starts to wear out then typically you'' not be stalling your engine you will be setting code '333' and stumbling when you have your foot to the floor but will idle and run fine at low loads.. the worse it gets then oyu can start setting more codes and stalling more often.. to the point that eventuslly it will start and run cold but wont run for crap hot and will start hard hot (long cranks)..
3. - IPR - the IPR is the injection pressure regulator itself.. this device opens and closes a valve which controls the pressure sent to the head rails.. the computer commands it at various duty cycles to accomplish this.. there is a little electric solenoid on the valve itself.. if the nut falls off of the back of the assembly than that little solenoid can vibrate all around (or fall off altogether) and you'll get wierd operations.. if this valve starts sticking or the wiring connections arent great you'll get wierd operations from it.. unfortunately for us with the T444E (as opposed to the ford 7.3).. our HPOP (and the IPR on the back of it) sit in the valley under the fuel bowl under the powered steering pump...
4. - ICP - this is the sensor that tells the computer what the actual HPOP pressure is.. if this goes bad you can get wierd operations as it can lie to the computer about actual pressure.. it can tell the comouter the HPOP pressure is 800 PSI when the computer wants only 600.. so the computer keeps turning down the IPR even though the ICP keeps saying 800... the computer can technically shut the engine down because of this "lie"... this is an easy one to test.. unplug the ICP and run the engine.. the ECM has a default set of parameters for the IPR that it will run when the ICP sensor goes "insane" or is unplugged (circuit fault).. of course you'll get a code and I think a WARN light but the engine will run and drive. (not great but it will)...
finally dont discount fuel pressure.. while injection pressure is important so is fuel.. there is a test point on the fuel regulator where you can plug in a fuel pressure test gauge.. if you still have the mechanical factory fuel pump your fuel pressure will bop up N down on the needle (I use a needle gauge and not digital) to the rhythm of the engine.. year 2000 was pivotal.. some got the 47 PSI spring others got the 62-65 PSI spring.. so you connect your gauge and watch the pressure.. if its still staying up when you stall you know fuel isnt your issue.. likely oil (or CPS)...
the CPS is another PITA.. if its running and suddenly dies... and you can repeat it.. you watch your RPM on the servicemaxx or even do a record-session... if you see your RPM signal drop to 0 or close to it before you hear the engine physically stop spinning then you can point yourself in that direction as it means the ECM lost RPM signal and wont fire the injectors.. and it wont set as code unless the CPS wiring goes open or shorted or super erratic.. as it simply thinks the engine was stalled.. in a stick shift you wouldnt want to set a code everytime the driver simply dumped the clutch and killed it (which would result in an instant 0 RPM from the CPS)...
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